1. Field of the Invention
The present invention relates to wireless communication networks. More particularly, the present invention relates to a system and method for managing communication in a wireless communication network.
2. Description of Related Art
Time Division Multiple Access (TDMA) systems, such as Global System for Mobile Communication (GSM), have a plurality of timeslots in a given time frame. For example in GSM, each TDMA time frame has eight timeslots. Conventionally, each timeslot is reserved for use by a particular communication device for receiving or transmitting user data from or to a base station in a cellular environment.
Digital mobile communication systems for voice such as GSM, and Digital Advanced Mobile Systems (DAMPS) have expanded very rapidly in recent years. In addition, great demand for data service has been created by mobile users due to wide spread acceptance of the Internet. General Packet Radio Service (GPRS), Enhanced Data rate for GSM (EDGE), and Universal Mobile Telecommunications Services (UMTS) are all being developed to accommodate data users in wireless networks. Schemes for the transmission of voice over fixed packet switch networks have also been developed in recent years and an increasing amount of voice traffic will be carried over packet switched networks in the future.
With the recent advancement in the digital mobile communication systems, various approaches have been developed to allow multiple communication devices to reuse a single timeslot in a frame, referred to as Multiple Users Reusing One Slot (MUROS) technology. MUROS technology allows pairing of two or more communication devices (e.g., up to four) to use one single timeslot to transmit or receive voice signals in the GSM, GPRS, EDGE wireless systems. Theoretically, MUROS technology enhances a cell capacity through pairing two or more communication devices onto a single timeslot. Therefore, MUROS may be able to at least double voice capacity of the wireless network without requiring additional Transmit and Receive radio resources (TRX).
The communication devices in the cell should be paired onto a single timeslot in such a way that link quality for either of the paired communication devices does not see a drastic degradation. For example, if upon pairing, the link quality sees a sudden degradation, then calls associated with the paired communication devices may get dropped. The link quality of the communication devices that are paired mainly depends on Bit Error Rate (BER) and Signal to Noise Ratio (SNR) characteristics of the communication devices.
Typically, communication devices with high SNR or similar power levels may form good candidates for sharing a single timeslot. As an example, two or more communication devices are assumed to be allocated a single timeslot based on their SNR values or power levels. In that case, if the communication devices in the cell do not have the same or similar power levels or high SNR values, then the power of individual communication devices is boosted before pairing to have acceptable Frame Error Rates (FERs). However, power boosting of the communication devices prior to pairing may add to the total interference in the wireless network and thus may introduce additional complexity to power control.
Further, in the currently known techniques, BER characteristics of the communication devices to be paired are not verified prior to allocating the single timeslot to the communication devices. As a consequence, the link quality of the communication devices may see a drastic degradation under paired conditions, thereby resulting in dropped calls. Additionally, the paired communication devices in the cell require boosting of power after being paired to maintain links and to have acceptable FERs.